为提高香菇酶解液的酶解效率和感官品质,研究了3种酶复合酶解香菇的较佳工艺。首先通过正交试验优化了纤维素酶的酶解条件,纤维素酶的较佳酶解条件为温度40℃、时间1 h、加酶的质量分数0.5%。然后以感官评分和α-氨基态氮含量为指标筛...为提高香菇酶解液的酶解效率和感官品质,研究了3种酶复合酶解香菇的较佳工艺。首先通过正交试验优化了纤维素酶的酶解条件,纤维素酶的较佳酶解条件为温度40℃、时间1 h、加酶的质量分数0.5%。然后以感官评分和α-氨基态氮含量为指标筛选出菠萝蛋白酶和风味蛋白酶2种蛋白酶,最后通过响应面试验优化了复合酶的较佳酶解条件。结果表明,3种酶同时酶解香菇液为较佳酶解方式,复合酶的较佳酶解条件为温度58.6℃、时间2.02 h、质量浓度15.24 m L/g(即超纯水体积与香菇粉质量的比例)。在此条件下得到的α-氨基态氮的密度为0.090 1 g/100 m L,感官评分为7.4,属于喜欢范畴。展开更多
A retrofitting technology using precast steel reinforced concrete（PSRC） panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system s...A retrofitting technology using precast steel reinforced concrete（PSRC） panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system surrounding the existing masonry building. The PSRC walls are well connected to the existing masonry building, which provides enough confinement to effectively improve the ductility, strength, and stiffenss of old masonry structures. The PSRC panels are prefabricated in a factory, significantly reducing the situ work and associated construction time. To demonstrate the feasibility and mechanical effectivenss of the proposed retrofitting system, a full-scale five-story specimen was constructed. The retrofitting process was completed within five weeks with very limited indoor operation. The specimen was then tested in the lateral direction, which could potentially suffer sigifnicant damage in a large earthquake. The technical feasibility, construction workability, and seismic performance were thoroughly demonstrated by a full-scale specimen construction and pseudo-dynamic tests.展开更多
以鲁西南地区雷电灾情资料、闪电定位资料、雷暴日资料、土壤电阻率资料、经济社会资料为基础,选取8个评价指标对雷电灾害频度预测进行研究,通过相关性分析,发现雷电流≥20 k A地闪密度以及总地闪密度与雷灾频度关系最密切,且通过了α=0...以鲁西南地区雷电灾情资料、闪电定位资料、雷暴日资料、土壤电阻率资料、经济社会资料为基础,选取8个评价指标对雷电灾害频度预测进行研究,通过相关性分析,发现雷电流≥20 k A地闪密度以及总地闪密度与雷灾频度关系最密切,且通过了α=0.01的显著性检验,土壤电阻率对应的相关系数次之,且通过α=0.05的显著性检验,雷暴日、第三产业比例、人口密度、人均GDP、农村人口比例相关性不密切。通过回归分析,建立2个雷电灾害频度预测方程,分别通过了α=0.05和α=0.1的F检验,利用2015年雷灾数据进行验证,平均误差较小,具有一定的指导性。展开更多
文摘为提高香菇酶解液的酶解效率和感官品质,研究了3种酶复合酶解香菇的较佳工艺。首先通过正交试验优化了纤维素酶的酶解条件,纤维素酶的较佳酶解条件为温度40℃、时间1 h、加酶的质量分数0.5%。然后以感官评分和α-氨基态氮含量为指标筛选出菠萝蛋白酶和风味蛋白酶2种蛋白酶,最后通过响应面试验优化了复合酶的较佳酶解条件。结果表明,3种酶同时酶解香菇液为较佳酶解方式,复合酶的较佳酶解条件为温度58.6℃、时间2.02 h、质量浓度15.24 m L/g(即超纯水体积与香菇粉质量的比例)。在此条件下得到的α-氨基态氮的密度为0.090 1 g/100 m L,感官评分为7.4,属于喜欢范畴。
基金Scientific Research Fund of Institute of Engineering Mechanics,CEA under Grant No.2016A06International Science & Technology Cooperation Program of China under Grant No.2014DFA70950National Natural Science Foundation of China under Grant Nos.51378478,51161120360
文摘A retrofitting technology using precast steel reinforced concrete（PSRC） panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system surrounding the existing masonry building. The PSRC walls are well connected to the existing masonry building, which provides enough confinement to effectively improve the ductility, strength, and stiffenss of old masonry structures. The PSRC panels are prefabricated in a factory, significantly reducing the situ work and associated construction time. To demonstrate the feasibility and mechanical effectivenss of the proposed retrofitting system, a full-scale five-story specimen was constructed. The retrofitting process was completed within five weeks with very limited indoor operation. The specimen was then tested in the lateral direction, which could potentially suffer sigifnicant damage in a large earthquake. The technical feasibility, construction workability, and seismic performance were thoroughly demonstrated by a full-scale specimen construction and pseudo-dynamic tests.
文摘以鲁西南地区雷电灾情资料、闪电定位资料、雷暴日资料、土壤电阻率资料、经济社会资料为基础,选取8个评价指标对雷电灾害频度预测进行研究,通过相关性分析,发现雷电流≥20 k A地闪密度以及总地闪密度与雷灾频度关系最密切,且通过了α=0.01的显著性检验,土壤电阻率对应的相关系数次之,且通过α=0.05的显著性检验,雷暴日、第三产业比例、人口密度、人均GDP、农村人口比例相关性不密切。通过回归分析,建立2个雷电灾害频度预测方程,分别通过了α=0.05和α=0.1的F检验,利用2015年雷灾数据进行验证,平均误差较小,具有一定的指导性。
